1. Field of Invention
The present invention relates to a gas generator for a restraining device that is suitable for airbag apparatus and the like.
2. Description of Related Art
A gas generator is known in which an ignition device is attached to one end in an inside of an elongated housing, a gas discharge port is provided at the other end, and a gas generating agent is charged into a space in the middle portion.
When the ignition device is actuated in such a gas generator, combustion advances from the gas generating agent located close to the ignition device toward the other end side, but since the gas generating agent is densely charged, it is necessary that gas generated by the combustion is guided to the gas discharge port, while the gas generating agent is burned.
U.S. Pat. No. 6,412,816 discloses a gas generator in which a tubular filtering system 4 is disposed inside an elongated housing 1, and the longitudinal axis of the filtering system 4 is arranged to match the housing axis.
One end of the housing is closed by a curved surface, and the exit ports 5 are formed in a circumferential wall in the vicinity of the closed end surface.
In the tubular filtering system 4, the opening at one end is abutted against the ignition device 2, the opening at the other end is abutted against the closed end surface, and the diameter of the tubular filtering system decreases continuously toward the closed end surface. Further, the filtering system is disposed from the opening at one end of the housing 1 to the closed end surface.
The gas generating mixture is charged into the tubular filtering system 4, the space between the tubular filtering system 4 and the housing 1 is an outflow chamber 7 serving as a gas flow channel space, and the gas flow channel space increases continuously in size toward the closed end surface side.